While Alzheimer’s is the most common form of dementia, there are many other dementias. While we have some understanding of the direct causes of the various dementias, we still understand very little about what triggers the processes that cause so much damage to the brain. Also we know very little about how to prevent these dementias, other than vascular dementia.
For most people that live with dementia, research is of little or no use. While medication can help temporarily, in the UK it’s prescriptions are quite restricted. This means that adapted environments and good quality support and care are the key tools to increase the well being of people with dementia.
This is the most common form of dementia. The chemistry and structure of the brain changes, leading to the death of brain cells, with more and more brain cells damaged as the disease progresses. While we understand the process of Alzheimer’s, we do not understand what triggers these changes to take place, or how to prevent it.
The progression of the disease follows a typical pattern through early, moderate and late stages. Understanding these stages can help carers to prepare themselves for the suport and care that is likely to be required in the various stages.
This is caused by a failing oxygen supply to parts of the brain, so causing brain cells to die. The symptoms of vascular dementia can occur either suddenly, following a stroke, or over time, through a series of small strokes (also known as TIAs – transient ischemic attack). Typically oxygen supply fails through the narrowing and blocking of the arteries in the brain. It is thought that, like cardo-vascular disease, the risk of getting vascualr dementia can be reduced through not smoking, healthy diet, and exercise. Where the stroke pattern is ‘little and often’ the disease progresses much like Alzheimer’s and it can be difficult in practice to distinguish between the two.
Lewy Body Dementia
This form of dementia gets its name from tiny spherical structures that develop inside nerve cells. Their presence in the brain leads to the degeneration of brain tissue. The distinguishing aspect of Lewy Body dementia is that the structures float arround for a while, then attach themselves to brain cells, then after a while they float again. While they are floating, the person appears to be less affected by the dementia. Over time, the time periods affected by the dementia get longer and longer, and the ‘normal’ periods shorter and shorter.
This pattern can be very confusing and upsetting for carers. Understand that this pattern cannot be controlled by the person with the Lewy Body dementia can perhpas help the carer to support the person flexibly, offering more support or less support as required. It can also help to understand the periods where the person seems ‘normal’ will get shorter and shorter and that is is an inevitable process.
In fronto-temporal dementia, damage is usually focused in the front part of the brain, and these parts of the brain affect people’s personality and behaviour. Depending on the level of damage, these changes can quite subtle or quite distinct. For example someone who was previously quite reserved can become quite uninhibited and behave in unexpected ways, and this can be very upsetting the for carers. It is really important to understand that the person with the dementia has no control over this behaviour and this can make it easier to accept the behaviour and try and support that person in a sympathetic way. Telling someone off because they behave in ways that are not normally acceptable is very unhelpful and will tend make things worse not better.
Korsakoff’s syndrome is a brain disorder that is usually associated with heavy drinking over a long period. Although it is not strictly speaking a dementia, people with the condition experience loss of short term memory.
Creutzfeldt- Jakob disease
Prions are infectious agents that attack the central nervous system and then invade the brain, causing dementia. The best-known prion disease is Creutzfeldt-Jakob disease, or CJD.
Causes of other dementias
There are many other rarer causes of dementia, including progressive supranuclear palsy and Binswanger’s disease. People with multiple sclerosis, motor neurone disease, Parkinson’s disease and Huntington’s disease can also be at an increased risk of developing dementia.